Fig. 4

Illustration of lipiodol-based cervical INL in a pig model. In this case, lipiodol-based cervical INL was introduced. Under ultrasonography guidance, the tip of the needle (white arrowhead) was advanced until reaching the center of the target lymph node (*) (A). An efferent lymphatic vessel (white arrowhead) at the left neck was opacified after a small amount of lipiodol injection (B); then, continue the lipiodol injection. Over time, lipiodol gradually shifted towards the left jugular vein angle over time (C). The lipiodol injection ceased when oil-dropped lipiodol entered the left brachiocephalic vein (white arrowheads; D). As the same, the lymph nodes (*), efferent lymphatic vessels, and right lymphatic duct (white arrowheads) at the right side of the neck were gradually opacified after the lipiodol injection (E). After INL, remove the needles and carry out the volume rendering reconstruction of post-lymphangiography CT to demonstrate the three-dimensional lymphatic structure, such as lymph nodes (*), lymphatic vessels (white arrowheads), and bilateral confluences of jugular venous angles (white arrows; F). Images were from Pig No. 7. Abbreviation: INL, intranodal lymphangiography; CT, computed tomography